Winmail.dat attachments in MailSite Express When viewing mail in MailSite Express, some messages contain an attachment named winmail.dat. This is a problem when sending mail in Rich Text Format (RTF), especially when using Microsoft Outlook 2000 or Microsoft Word. winmail.dat contains extra information used to preserve message formatting. The file is normally very small. However, MailSite Express cannot open this file.

Further information, along with possible solutions, can be found in the following Microsoft Support Documents:

http://support.microsoft.com/default.aspx?scid=kb;EN-US;q269186

http://support.microsoft.com/default.aspx?scid=kb;en-us;Q197064